'American Hero' is the novel behind a new Robert De Niro film. But the author has been told that he can't claim credit.

And, legality aside, is it ethical for a film company to disallow a book it optioned from legitimately promoting itself as the basis for the movie?

That King Solomon-like dilemma has been simmering behind the scenes in a project involving some of the most principled artists in film--Robert De Niro, Dustin Hoffman, director Barry Levinson ("Rain Man," "Avalon") and writer David Mamet.

Larry Beinhart's novel "American Hero," a satirical work suggesting that then-President George Bush created the Gulf War to boost his approval ratings, was published in 1993 to glowing reviews. It was optioned by De Niro's production company, TriBeCa, and New Line Cinema for $25,000 and attracted Hoffman, Levinson and eventually Mamet to do a rewrite after the first draft of the screenplay was rejected.

Mamet turned Bush and the Gulf War into a fictional president and fictionalized war in Albania. The president is also now caught dallying with a Girl Scout. A war is whipped up to deflect attention from a wobbly White House.

The New Line film, now retitled "Wag the Dog," opens in December, and the film company has refused the expected paperback tie-in with Ballantine Books. The publisher and the author were hoping to capitalize on the book's genetic relationship to the film. New Line says the movie is no longer the book, so no direct association is allowed.

"It's unfair," says Clare Ferraro, senior vice president and publisher of Ballantine Books. "We all recognize the differences between the book and the movie. But we also recognize the similarities. And the credit is going to be right up there on the screen, 'Based on the novel "American Hero" by Larry Beinhart.' But they seem to not want to go the next step."

The filmmakers say they are honoring the artistic process that created something new out of something old and that that difference should be respected.

"We consider it to be an original screenplay by Mr. Mamet. To say that 'Wag the Dog' is based on the book 'American Hero' by Larry Beinhart would be totally inaccurate," says Jane Rosenthal, co-founder of TriBeCa and one of the film's producers.

"I had New Line option the book, which I loved. Hilary Henkins wrote a script which Barry didn't care for, though he liked the premise. It totally became a collaboration between Levinson and Mamet. The characters in the movie are not the characters that Mr. Beinhart created. So we are kind of being rather honest to say the movie, its story, its dialogue is 100% different, aside from the basic premise."

The book people argue that honoring the artistic process means respecting the seminal contribution of the writer who created the novel that launched the film.

"You have two brilliant writers, Larry Beinhart and David Mamet. You have the basic concepts, which are still intact. There should be a spirit of cooperation and mutual respect that one writer has for another," says Joy Harris, Beinhart's New York-based literary agent, who has also represented cross-over books like "How to Make an American Quilt" and "Apollo 13."

"A movie was made, based on this book, that they expect to be a great success. And we all know how authors are treated in these situations: badly."

Creative Artists Agency literary agent Bob Bookman is wary of facile judgment calls. "It's so hard to evaluate. It's a value judgment. How much did they change? Could a reasonable reader pick up the book and feel that they have somehow been misled?"

Mamet has taken most of the heat for the "Wag the Dog" imbroglio, including a scathing report in a New York paper saying he was single-handedly responsible for excommunicating Beinhart's book. Henkins, for her part, had to resort to guild arbitration to secure screen credit with Mamet, who was being listed solo in New Line's publicity material.

"In the 22 years I've been at this, this is only the second time I've seen this," agent Harris says. "The other was when they wouldn't allow a book tie-in with 'Shoeless Joe' by W.P. Kinsella, the basis for 'Field of Dreams.' And I've represented many books. This is because nobody wanted to upset Mr. Mamet."

Rosenthal bristles at the attacks on Mamet. "I think it would be a disservice to Larry Beinhart to say that the movie is in a sense a true extension of the book. And reciprocally to David Mamet it would be a disservice to say he adapted that book, which he didn't do either. It's best to leave both pieces exist independently of one another," says Rosenthal. (Mamet would not respond to inquiries regarding this story.)

But New Line has come under vocal fire from the book's publisher, agent and author.